1. Field of the Invention
The present invention relates to a battery cell and electronic apparatus with electrostatic discharge protection, especially to a battery cell and electronic apparatus utilizing a conditional conducting path to achieve electrostatic discharge protection.
2. Description of Related Art
Natural material may obtain or lose electrons through certain ways, e.g. friction or induction. Such kind of electrons is called static electricity. When positive or negative electrons accumulate gradually, a potential variation is cause a large current which may damage an electronic device in the discharge path permanently, build between the accumulated electrons and the environment surrounding them. Then a transfer phenomenon between different potentials through a discharge path occurs. This phenomenon is the so-called electrostatic discharge (ESD). This instant discharge may affect its circuitry function, and induce a malfunction of it.
However, it's hard to avoid the ESD phenomenon. During the process of manufacturing, producing, assembling, testing, storing and transporting an electronic device or an electronic system, electrostatic electricity will be unavoidably accumulated in the human body, instrument, storage equipment and/or the electronic device itself. As a result, when these objects contact to each other, a discharge path is formed and the electronic device or electronic system may suffer the damage from ESD. Besides, since more and more electronic products use the design of metal casing to comply with the requirement of specification (e.g. requirement of shielding magnetic interference) or to improve their exterior appearances, electrostatic charge will be more easily accumulated on the metal casing and consequently cause the ESD phenomenon.
Presently most designers strictly control the manufacturing environment free from the accumulation of electrostatic electricity and, more importantly, add the design of ESD protection to the electronic products, so as to prevent the electronic products at end users' hands from ESD damage. As to the design of ESD protection, one can improve the integrated circuit's tolerance to ESD and, most fundamentally, enhance the ESD protection through the design of the discharge path of ESD.
The prior arts (Taiwan patent number M345272, M345273 and M339787) disclose a design of casing that can discharge electrostatic electricity through a path to a system ground which then passes the electrostatic electricity to the ground terminal of a power socket through an adapter. This design can't provide ESD protection when the system ground doesn't connect to the adapter or the adapter doesn't connect to the ground terminal, and the circuit within the casing is still exposed to ESD damage.
Therefore, a further improvement to the design of ESD protection is necessary.